Method and mechanism for transporting work

ABSTRACT

There is a module conveyance mechanism  1  projected, which comprises: lift means for transfer  6 , in which the module constructed in a subline SL is made to move through a lower part than a floor side FL of a mainline ML; a slide mechanism  5 , wherein the module is made to move through a lower part than the floor side of a mainline ML parallel to the floor thereof; the lift means for assembly  4 , in which the module transferred from the slide mechanism  5  is made to rise to the assembly zone of the body F.

FIELD OF THE INVENTION

The present invention relates to a work conveyance method for conveyinga work constructed in a subline to an assembly zone for making a vehiclebody in an assembly line thereof, and a work conveyance mechanism forthe same.

BACKGROUND ART

As for the vehicle assembly line to assemble an automobile, it isconstituted with a mainline, wherein various parts are assembled intothe body of the automobile that is moved along a conveyance line withbeing hung from a hanger or being set on a pallet, a subline, whereinthe work that contains a plurality of parts is constructed with, and thework conveyance mechanism, in which the work that is constructed in thesubline is conveyed to the assembly zone for the automobile. Further, asthe part that is assembled on the body, it is mentioned that acommunication line such as a wiring for electric system or the like,interior parts such as installment panel or a seat, suspension systemparts such as an engine or suspension and exterior parts such as arear-vision mirror or a windshield wiper, and among these kind of partsabove mentioned, the engine, the suspension or the like can be mentionedas a work put together into in the subline.

Hereupon, as a conventional embodiment for conveying the workconstructed in the subline to the assembly zone for the body of theautomobile, there can be Japanese patent Laid-open publication1994-135538 mentioned.

As for the work conveyance mechanism indicated in Japanese patentLaid-open publication 1994-135538, it is the work conveyance mechanism,in which the body of the automobile moving along a ceiling side pathwith being hung from the hanger device is set up an internal combustionengine to, and which consists of a floor side path that is laid on andone part thereof seems to repeat with the ceiling side path; aself-propelled trolley that is transferred along the floor side path;and a device of ascend and descend for rising the internal combustionengine loaded onto the trolley to the assembly zone.

With the work conveyance mechanism constituted in such manner, in thearea that the ceiling side path is superposed on the floor side path,there are moved the hanger device and the trolley in one body combined,because a transmission part of the hanger device that is to move isengaged with a power receiving part of the trolley, and more, there isthe internal combustion engine supplied in the assembly zone, to whichthe device of ascend and descend on the trolley is let rise.

However, it is necessary in the work conveyance mechanism for thetrolley to be provided with means, by which the trolley is letself-propel and the internal combustion engine is let rise thereto sothat the trolley has become large-scale and complicated in structure aswell.

When the trolley extends in covered area and becomes complicated, thework efficiency falls to that extent because a working space of a workerassembling works to the body becomes narrow, and also there is apossibility to constitute an obstacle in safety of the work.

Beside, in order to let the work efficiency of automobile assembly lineimprove, it is necessary to be constituted that the floor side path isto be formed widely and there are many large-sized trolleys lying movedin a cycle.

However, when the trolley becomes large-scale and the floor side path isextended, there are problems that the use efficiency of the floor spaceis let fall and the degree of freedom according to the automobileassembly line is ruined as well.

DISCLOSURE OF THE INVENTION

Accordingly, it is a problem to be settled of this invention that theworks can be conveyed by a simple constitution immediately and the workconveyance method and the work conveyance mechanism are offered, inwhich they do not ruin the work environment of a worker performing anassembly work to the body.

As for the invention according to claim 1 of the present invention inorder to solve the problem above mentioned, it is the work conveyancemethod to convey the work constructed in the subline to the assemblyzone, which includes: a delivering process, in which the work isdelivered from the subline; a moving process, in which the work is movedparallel to the mainline in a lower part than the floor side of themainline and supplied to the supply position that is underneath theassembling zone; a lifting process, in which the work is let rise fromthe supply position to the assembling zone.

With the work conveyance method constituted in this way, it is possiblethat the work delivered from the subline is supplied to the assemblyzone from the part that is via under part of the mainline lying on thefloor. Accordingly, because a conveyance mechanism such as a rail or aturn mechanism is not laid on the floor side of the mainline, a workingarea of a worker can be secured fully and the efficiency of installationworking of the work can be let improve.

Besides, as for the invention according to claim 2, there is a workconveyance mechanism suggested, wherein the work constructed in thesubline is conveyed to the assembly zone of the body in order toassemble the work to the body moving on the mainline, which comprises amoving means, in which the work transferred from the subline is let moveunder the floor of the mainline and supplied to a supply position underthe assembly zone; a lifting means for assembly, in which the work isrisen from the supply position to the assembly zone.

With the work conveyance mechanism constituted in this way, the worktransferred from the subline can be moved under the floor of themainline through the moving means. And also the work can be let rise tothe assembly zone of the body from the lower part through the liftingmeans mentioned above. Accordingly, because the conveyance mechanismsuch as rail or a turn mechanism is not laid by the floor side of themain line, a working area of a worker can be sufficiently secured andthe efficiency of installation work of work can be let improve.

Further, as for the invention according to claim 3, there is suggestedthe work conveyance mechanism according to the claim 2 in which a movingmeans possesses a slide mechanism, in which the work is moved parallelto the floor side under the same; and a lift means for transfer, inwhich the work can be moved up and down in order to transfer to theslide mechanism from the subline.

With the work conveyance mechanism constituted in this way, the worktransferred from the subline is once took down in the lower part of thefloor with the means for transfer and after moved therein, the work canbe supplied to the assembly zone. Accordingly, even if the mainline andthe subline are laid in the same floor side, the work constructed in thesubline can be supplied to the body by way of the lower part of thefloor.

And, as for the invention to be concerned with the claim 4, there issuggested the work conveyance mechanism according to the claim 3 inwhich the lift means for transfer is provided with a turn means forletting a direction of the work turn a fixed angle.

According to the work conveyance mechanism that is constituted in thisway, the work can be smoothly assembled to the body even if the worktransferred is different in a direction from that to be assembled to thebody.

Besides, as for the invention according to claim 5, there is suggestedthe work conveyance mechanism according to the claim 3 or the claim 4,wherein the slide mechanism possesses a first slide part in which apallet loaded with the work is to be moved to the supply position and asecond slide part which is arranged a fixed distance below from thefirst slide part, and the lift means for assembly can move from thesupply position to a return position at which the pallet is returned inthe second slide part.

According to the work conveyance mechanism that is constituted in thisway, it is possible that the work is carried in the first slide part andafter it is assembled to the body, an empty pallet is moved in thesecond slide part, so that the empty pallet can be quickly return to thesubline. Accordingly, because the pallet that is going to convey thework can be circulated quickly or smoothly, it is possible that theconstructing of the work and the assembling of the work to the body areperformed by the good efficiency.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a front elevation showing the work conveyance mechanism of theembodiment of this invention.

FIG. 2 is a ground plan to show the work conveyance mechanism of theembodiment of this invention.

FIG. 3 consists of (a) and (b), in which (a) is the side view whichlooked at the side view which looked at slide system from the side ofthe lift means for assembly and (b) is a slide system from a side of thelift means for transfer.

FIG. 4 consists of (a) and (b), in which (a) is a ground plan to explainthe receipt process when a pallet is received from the subline (b) is afront elevation explaining receipt process.

FIG. 5 consists of (a) and (b), in which (a) is an illustration to showa turn of a receipt part and (b) is an illustration to explain a descentof a receipt part and a movement of pallets from a receipt part to theslide mechanism.

FIG. 6 consists of (a), (b) and (c), in which (a) is an illustration toshow movement of pallets from the slide mechanism to the lift means forassembly, (b) is an illustration to show movement of pallets from thesupply position to the assembly zone and (c) is an illustration to showmovement of empty pallets from the assembly zone to the return position.

FIG. 7 is an illustration to show the state that the pallet moved to aguide portion for return of the lift means for transfer.

BEST MODE FOR CARRYING OUT THE INVENTION

Referring now to a preferred embodiment, this invention will bedescribed in further detail with reference to the accompanying drawings.

FIG. 1 is a front elevation of the work conveyance mechanism in theembodiment, and FIG. 2 is the ground plan, which is looked at the workconveyance system from the top. Hereinafter, the work is explained as arear suspension RS in the embodiment. Besides, a direction to which thebody F moves with the mainline ML (a direction gone to right from leftshown in FIG. 1) is determined as the front direction.

As for the mainline ML of the embodiment, as shown in FIGS. 1 and 2,there is suggested a line in which a suspension member such as a rearsuspension RS or an engine is assembled to the body F that is hung froman overhead conveyor OC that is moved therewith, wherein the body isconveyed from the left to the right in FIGS. Further, there is the workconveyance mechanism 1 provided with, more underneath than the floorside FL having the mainline ML, in which the rear suspension RSconstructed in the subline is assembled to the body F.

Hereupon, as for the subline SL, it is laid at a right angle to themainline ML, and in which fixed members are assembled to the rearsuspension RS during conveying of the pallet P by a chain conveyer 2 andconstructing thereof is finished by the pallet P arriving at theterminal SE of the subline SL.

The work conveyance mechanism 1 comprises: the lift means for assembly4, through which the rear suspension RS is let rise to the body F from abasement pit 3 that is arranged along the mainline ML; the slidemechanism 5, in which the rear suspension RS is let move parallel to thefloor side FL to the lift means for assembly 4 for supply in the lowerpart than the floor side FL; the lift means for transfer 6, by which theslide mechanism 5 and the subline SL are connected. Further, the movingmeans according to the claims of this invention is constituted with boththe slide mechanism 5 and the lift means for transfer 6.

Hereupon, in the work conveyance mechanism 1 and the subline SL, therear suspension RS loaded with the pallet P is carried and this pallet Pconsists of a tabular member and has a protruding point part 7 a.

Still more, a fence 8 is arranged to an opening part of the basement pit3 and prevents workers from falling.

Subsequently, it is described that each constitution element of workconveyance mechanism 1.

First, as for the slide mechanism 5, there are a first slide part 12 anda second slide part 13 provided, which are made of a chain conveyerestablished with a main frame body 11 to form on a base 10 (shown inFIGS. 1, 2 and 3(a), (b)).

The first slide part 12 has a rotation axis 14 a of the lift means forassembly 4 side and a rotation axis 14 b of the lift means for transfer6 side, and, as for the axis 14 a and the rotation axis 14 b, they aresupported, respectively through bearing by side frames 15 a, 15 b, 15 cof the main frame body 11. Furthermore, the rotation axis 14 a isequipped with a sprocket 16 a, 16 a and the rotation axis 14 b isequipped with a sprocket 16 b, 16 b, respectively and a chain 17 bindseach opposing sprocket 16 a and sprocket 16 b.

Moreover, there is a pulley 18 a formed in the side frame 15 a side ofthe axis 14 a to show it in FIG. 3(b) and which drives the chain 17 bycommunicating a turn of a motor for driving of slide mechanism 19arranged at the lower part of the main frame body 11 to this pulley 18 athrough a belt 20 a.

On the other hand, as shown in FIG. 3(a), there is the pulley 18 bprovided which is made for the side frame 15 a side of the rotation axis14 b and communicates a turn of the rotation axis 14 b with drive ofchain 17 to the second slide part 13 through the belt 20 b.

Similarly, the second slide part 13, as shown in FIGS. 3(a) and (b),comprises: the rotation axis 21 a or the rotation axis 21 b supportedwith the side frame 15 a, 15 d and 15 e: two sprockets 22 a arrangedaround the rotation axis 21 a; two sprockets 22 b arranged around therotation axis 21 b; and the chain 23. The chain 23 being hung and woundtightly around each interval formed each sprocket 22 a and each sprocket22 b, which stand opposite to each other.

Besides, a pulley 24 a is made for the side frame 15 a side of therotation axis 21 b (as shown in FIG. 3(a)) and communicates a turn ofthe rotation axis 14 b of the first slide part 12 to the pulley 24 a byputting the belt 20 b with the pulley 24 a and the pulley 24 b arrangedunderneath. Moreover, the pulley 24 c being a thing to keep a tension ofthe belt 20 b, and the pulley 24 b and the pulley 24 c are bothsupported by the side frame 15 a.

Accordingly, a turn of the rotation axis 14 b is communicated to thepulley 24 a through the belt 20 b when the chain 17 of the first slidepart 13 is driven, so that the rotation axis 21 b turns, and the chain23 of the second slide part 14 is driven.

Subsequently, the lift means for transfer 6 is described.

The lift means for transfer 6, as shown in FIGS. 1, 2 and 4 (a), (b),has a transfer part 31, at which the rear suspension RS is received fromthe terminal SE of the subline SL, and the lift for transfer 32 to letmove from the same height of the belt conveyor 2 of the subline SL toheight of the first slide part 12 of a movement means 5 up and down.Furthermore, there is provided a turn means 33 formed between thetransfer part 31 and the lift for transfer 32, by which directions ofthe rear suspension RS and the pallet P are to be arranged at turning 90degrees.

There is provided the transfer part 31 having both a slide part fortransfer 34 which is made of a chain conveyer for transferring of therear suspension RS therein from the subline SL, and a slide part forreturn 35 which is located in the lower part of the slide part fortransfer 34 and utilized in returning an empty pallet P after the rearsuspension RS put on the pallet is assembled to the body F.

The slide part for transfer 34 has a chain 37, as shown in FIG. 2,comprising: an rotation axis 14 c, 14 d supported by the side flame 36a, 36 b and 36 c; a sprocket 16 c formed with an rotation axis 14 c; asprocket 16 d formed with an rotation axis 14 d; a chain 37. The chain37 has being hung and wound tightly around each interval formed eachsprocket 16 c and each sprocket 16 d, which stand opposite to eachother. The chain 37 communicates a turn of a motor of transfer part fordrive 40 fixed in lower part frame 39 of the transfer part 31 to apulley 18 c through belt 20 c and drives it by spinning the rotationaxis 14 c fixed in the pulley 18 c.

On the other hand, a pulley 18 d is made for a side frame 36 a side ofthe rotation axis 14 d and communicates a turn of the rotation axis 14 dwith drive of the chain 37 to the slide part for return 35 through abelt 20 d.

Similarly, a slide part 35 for return, as shown in FIG. 1 and FIG. 4(b),comprises: the rotation axis 21 c and the rotation axis 21 d; a sprocket22 c formed around the rotation axis 21 c; a sprocket 22 d (not shown)formed around the rotation axis 21 d; and a chain 41. The chain 41 hasbeing hung and wound tightly around each interval formed each sprocket22 c and each sprocket 22 d, which stand opposite to each other.

The chain 41 is driven, as shown in FIG. 1, by communicating a turn ofthe rotation axis 14 d of the slide part for 34 to a pulley 42 a madefor the side frame 36 a side of the rotation axis 21 d. Moreover, thebelt 20 d is put between the pulley 42 a and a pulley 42 b fixed in theside frame 36 a, and it is kept tension in addition to above by a pulley42 c.

As for the turn means 33, it comprises: several tires 43 fixed in lowerpart frame 39 of the transfer part 31; a motor (not shown) to let drivetire 43; a rail 44 like ring for guiding a turn movement of tire 43 (cf.FIG. 2). A quantity of turn of the turn means 33 is controlled by a turnnumber of the motor, but the turn means 33 can control the quantity ofturn of the tire 43 by making a sensor for position search.

Subsequently, the lift means for assembly 4 is described.

As for the lift means for assembly 4 is described, as shown in FIG. 1and FIG. 2, it comprises: a table for assembly 51 to receive the palletP which carried the rear suspension RS that has been sent from themovement means 5; an X axis stage 52 letting the table for assembly 51move to a move means 3 side; a lift for assembly 53 lets the table forassembly 51 and the X axis stage 52 move up and down.

The table for assembly 51 has: two ditches 54 formed along movingdirection of the pallet P; a plurality of rollers 55 arranged along theditches 54: a protruding part 56, the protruding part 56 having a rolefor stopping the pallet P by contacting with the point part 7 a of thepallet P moving form the slide mechanism 5. And, as for this protrudingpart 56, there is it arranged on a rail 57 formed in a central part ofthe table for assembly 51, which is movable thereon and is connectedwith an air cylinder (not shown), and it is possible to send the emptypallet P out in the second slide part 13 by letting the protruding part56 move along the rail 57 to the slide mechanism 5 side after the rearsuspension RS is assembled to the body. Still more, the protruding part56 serves as a search means to confirm a position of the pallet P, it isjudged for the pallet P to be introduced into the table for assembly 51by a control portion (not shown) when the point part 7 a of the pallet Pabuts thereon.

The X axis stage 52 is driven by an air cylinder 58 formed on the lift53 and lets the table for assembly 51 move to the front or backdirection along two slide bars 59.

There is provided the lift for assembly 53 letting the table forassembly 51 move to a fixed position and move a second lift 53 b forindependence with a first lift 53 a. Hereupon, as for the fixed positionabove mentioned, it is given that a supply position receiving the rearsuspension RS conveyed from the first slide part 12 of the slidemechanism 5 (cf. FIG. 6(a)), a waiting position for a chance being inthe fixed distance of the upper part from the floor side FL of the mainline ML, wherein the rear suspension RS is stood by, the assembly zonein which the rear suspension RS is assembled to the body F (cf. FIG.6(b)) and the return position from which the empty pallet P afterassembling the rear suspension RS is returned to the second slide part13 of the slide mechanism 5 (cf. FIG. 6(c)).

In next, a procedure in which the rear suspension RS is assembled to thebody F using the work conveyance mechanism 1 is described mainly onmovement of the pallet P.

First, as the transfer process, the pallet P on which the rearsuspension RS constructed in the subline SL is carried is transferred toa slide part 34 of the lift means for transfer 6 that stood by at theupper part, which is shown in FIG. 4(a) (b). At this point, there isprovided a stopping means 60 a, 60 b for stopping the pallet P formed ina space between two chains 37 and 37, which let the pallet P stop on theslide part for transfer 34 by letting a stopper pin project toward thepallet P from the same.

When the pallet P stops on the slide part for transfer 34, as shown inFIG. 5 (a), the turn means 33 is driven and turns the transfer part 31by 90 degrees in clockwise direction.

Subsequently, as shown in FIG. 5(b), the lift for transfer 32 is loweredand lets the slide part for transfer 34 of the transfer part 31 and thefirst slide part 12 of slide mechanism 5 stand in line on the straightline. Then stopping means 60 a, 60 b remove the rock state of the palletP and the pallet P is conveyed from the slide for transfer 34 to thefirst slide part 12.

Hereupon, there is provided a stopping means 60 b made for the liftmeans for assembly 4 side of the first slide part 12 (cf. FIG. 2), andthe pallet P conveyed in the first slide part 12 stops by the stoppingmeans 60 b.

As mentioned above, while the pallet P stops in the first slide part 12,the actuator 58 of the X axis stage 52 of the lift for assembly 4 isdriven and the first table for assembly 51 is approached to the firstslide part 12, which is shown in FIG. 6 (a). Then, because the stoppingmeans 60 b removes a rock state of the pallet P by a signal of thecontrol part, the pallet P moves from the first slide part 12 to thetable for assembly 51 by that the point part 7 a thereof abuts on theprotruding part 56. Still more, a process in which the pallet P is movedfrom the slide part for assembly 34 to the table for assembly 51 isturned into the moving process described in range of the claim of thepresent invention.

And, when the point part 7 b of the pallet P sticks to the protrudingpart 56, so that the pallet P stops, as well as the table for assembly51 comes back to an original position, the lift for assembly 53 rises asa rising process and the pallet P ascends by the position for waitingfor a chance, which is a fixed distance lower of that of the assemblyzone to body F. In this place, by a signal from the control department,the lift for assembly 53 rises more after a worker identifies the body Fand the rear suspension RS and; lets the pallet P move to the assemblyzone of the body (shown in FIG. 6(b)). So a worker assembles the rearsuspension RS carried by pallet P in the body F.

When the assembling to body F of the rear suspension RS is finishednext, the lift for assembly 53 is lowered with carrying the empty palletand lets the table for assembly 51 move to the return position thatshows in FIG. 6(c).

Then the protruding part 56 of the table for assembly 51 moves along therail 57 and the empty pallet P is pushed to the second slide part 13.And then, the empty pallet P pushed to the second slide part 13 movesalong the second slide part 13 until it is stopped by the stopping means60 a (cf. FIG. 3(a)) which is formed in the axis 21 b side of the secondslide part 13.

Hereupon, after confirming that the second slide part 13 and the slidepart for return 35 of the lift means for transfer 6 have stood in a lineon the straight line, the control department removes a rock of thestopping means 60 a and, as shown in FIG. 7, the pallet P is conveyedfrom the second slide part 13 to the slide part for return 35.

Furthermore, in the slide part for return 35, the stopping means 60 alets the pallet P stop (cf. FIG. 4(b)). Then, the lift for transfer 32works, and the slide part for return 35 rises till it has the sameheight of a chain conveyer for return 60 formed in the lower part of thechain conveyer 2 of the subline SL. When the slide part for return 35 isrisen thereto, the turn means 33 is driven and lets the slide part forreturn 35 turn 90 degrees in counterclockwise direction. Then, thepallet P is given back from the slide part for return 35 to the chainconveyer for return 60, because the chain conveyer for return 60 and theslide part for return 35 stand in line on the straight line, by removinga rock of the stopping means 60 a.

The pallet P returned by the chain conveyer for return 60 is conveyed toan initial point of the subline SL, and it is transferred here on thechain conveyer 2.

The pallet P which gives back to the initial or starting point of thechain conveyer 2 in this way is conveyed again by the chain conveyer 2,and new rear suspension RS is constructed thereon.

Because there is such work conveyance mechanism 1, in which the rearsuspension RS is supplied to the body F from the lower part than thefloor side FL of main line ML, there is no place on the floor, in whichthe conveyance mechanism complicated such as a rail for transfer, adrive means for transfer or the like is laid, so that a worker withoutminding steps can perform a work for assembly to the body F with goodefficiency.

Moreover, because the pallet P to be loaded with the rear suspension RSis made with simple constitution, the pallet P not only can becirculated immediately, but also has flexibility to correspond tochanges of the subline SL.

Still more, the present invention is not limited to an embodiment and itcan be applied broadly. For example, a work to convey may be an engineand a door instead of the rear suspension RS.

Besides, it can be also constituted that the subline SL is laid in lowerpart of the floor side FL of the mainline ML and the rear suspension RSsupplied to the assembly zone of the body F through the slide mechanism5 and the lift means for assembly 4.

Furthermore, the subline SL is not been there provided, it is good asthe work conveyance mechanism to supply the work to be carried in fromoutside factories for the body F from the lower part than the floor sideFL of the mainline ML.

And, it is possible that the first slide part 12 or the like isconstituted with a belt conveyor so that a work is conveyed not to usepallet P

Industrial Applicability

This invention consists of the mechanism for conveying the work, inwhich respectively, a work transferred from the subline is made move tothe lower supply position than the floor side of the main line and thework is risen to the assembly zone by the lift means for assembly fromthe supply position. Accordingly, because the work conveyance mechanismis not laid on the floor side, a worker can perform a work for assemblywith good efficiency smart and safely.

Besides, there is provided the move means constituted with both theslide mechanism to make the work move parallel to the floor sidethereunder and the lift for transfer means conveying the work to top andbottom direction in order to make the same move in the slide mechanism.Accordingly, even if the mainline and the subline are laid on the samefloor side, the work constructed in the subline can be supplied to thebody from under the floor.

And, when an installation direction of the body is different from adirection of the work conveyed on the subline, because there is the turnmeans formed in the lift for transfer means, by which the direction ofthe work is arranged, the work for assembly to the body can be performedimmediately.

Beside, as for the slide mechanism, it is constituted with the firstslide part to let the pallet loaded with the work move to the supplyposition and the second slide part to be arranged in a fixed distanceunder the first slide part and as for the lift for assembly means, whichis constituted that it is movable from the position of the assembly zoneto the place for returning the empty pallet, so that, it is possiblethat the pallet carried the work is moved in the first slide part, andthe empty pallet after assembling the work to the body is moved in thesecond slide part. Accordingly, the constructing or assembly of the workand the assembling the work to the body can be performed at higherefficiency.

What is claimed is:
 1. A work conveyance method, in which a work loaded on a pallet constructed in a subline is conveyed to an assembly zone of a body moving along a mainline, which includes: a transfer process, in which the pallet loaded with the work is transferred from the subline; a moving process, in which the pallet loaded with the work is moved in a lower part than a floor side of the mainline, and is moved parallel to the floor side of the mainline until the pallet is stopped when a protruding point part of the pallet is contacted to a protruding part of an assembling table on a lifting means so as to be supplied to a supply position that is underneath said assembly zone; and a lifting process, in which the work is lifted from said supply position to said assembly zone.
 2. A work conveyance method according to claim 1, further comprising a turning process wherein said pallet loaded with said work is turned 90 degrees by a turn means provided on a slide part for transfer.
 3. A work conveyance mechanism wherein work loaded on a pallet constructed in a subline is conveyed to an assembly zone of a body in order to assemble the work loaded on the pallet to the body moving on a mainline, which comprises: a moving means, in which the pallet loaded with work is transferred from the subline on a floor side of said mainline, is made to move under the floor of said mainline until the pallet is stopped when a protruding point part of the pallet is contacted to a protruding part of an assembling table, and is supplied to a supply position under the assembly zone; and a lifting means, in which the work is lifted from said supply position to said assembly zone, wherein the lifting means includes the assembling table.
 4. A work conveyance mechanism according to claim 3, further comprising a turn means provided on a slide part for transfer for turning said pallet loaded with said work 90 degrees.
 5. A work conveyance mechanism, wherein work loaded on a pallet constructed in a subline is conveyed to an assembly zone of a body in order to assemble the work loaded on the pallet to the body moving on a mainline, which comprises: a moving means, in which the pallet loaded with said work transferred from the subline, is made to move under the floor of said mainline uniil the pallet is stoppped when a protruding point part of the pallet is contacted to a protruding part of an assembling table and is supplied to a supply position under the assembly zone; and a lifting means in which the work is lifted from said supply position to said assembly .zone, wherein said lifting means includes said assembling table, wherein said moving means comprises: a slide mechanism, in which the work is moved parallel to said floor side thereunder; and a lift means for transfer, in which said work can be moved up and down in order to transfer to said slide mechanism from the subline.
 6. The work conveyance mechanism according to the claim 5, wherein said lift means for transfer is provided with a turn means for letting a direction of the work turn a fixed angle.
 7. The work conveyance mechanism according to the claim 5 or the claim 6, wherein said slide mechanism possesses a first slide part in which a pallet loaded with said work is to be moved to said supply position and a second slide part which is arranged a fixed distance below from said first slide part, and said lifting means can move from said assembly zone to a return position at which said pallet is returned in the second slide part. 